Testing of advanced components, materials, and coatings under extreme conditions that directly simulate engine operation is very costly. In most cases it involves the installation of the test article(s) in a special test engine in the case of aircraft engines, or in an operating gas turbine in the case of industrial gas turbines.
Use of a special test engine is extremely expensive. The cost of operating a test aircraft engine can run as high as $10,000 per operating hour. Since the test article must be tested for thousands of hours to meet flight certification, full life engine testing must be reserved for final testing of hardware for qualification. Therefore a low-cost testing facility is needed that can test this hardware during the experimental, high risk phase of development, and where failure to the test article does not have the potential to cause significant and costly damage to the test facility.
For industrial gas turbines, an existing operating gas turbine may be used. However, even this approach results in high costs due to uncertainty of the test article's performance, life, and potential for destructive failure, and the resulting impact on power plant's repairs, operability, and availability.
Existing testing facilities for testing hot section material systems are generally categorized as “burner rigs”. They typically use hot flame impingement onto the test article(s) to ascertain material/coating durability under hot conditions. While these burner tests are more easily accomplished than full engine testing they exclude some of the effects that induce material and/or coating failures like thermal mechanical failure in the base metal, coating spallation due to high thermal gradients, erosion due to high velocity flow, corrosion degradation due to trace elements in fuel at operating temperatures and pressures, ability to apply mechanical loads, and radiation loads in the combustor. It is desirable therefore to provide a test facility that effectively subjects test articles and materials to high heat and mechanical loads, high thermal gradients, high flow velocity environments, and other conditions exemplary of gas turbine engines. Furthermore, the test facility must be sufficiently scaled to meet cost and operability requirements.
There are additional testing problems associated with testing hardware intended for advanced engines that are yet to be developed. In this case, existing engines cannot provide the operating temperatures and pressures that this hardware will endure in the advanced engine. Again, a test facility that can provide these test conditions at low cost would greatly increase design confidence while reducing the life cycle cost for advanced engine development.